1. package Widgets.Input_Boxes.Constraints is 
  2.  
  3.     -- Returns 'newstr' only if it contains the basename of a file, without an 
  4.     -- extension or path. If 'newstr' contains any invalid filename characters, 
  5.     -- a path, or a dot for an extension, then 'curstr' will be returned. 
  6.     function Basename_Only( curstr, newstr : String ) return String; 
  7.  
  8.     -- Returns 'newstr' only if it contains a filename, without a path. If 
  9.     -- 'newstr' contains any invalid filename characters or a path, then 
  10.     -- 'curstr' will be returned. 
  11.     function Filename_Only( curstr, newstr : String ) return String; 
  12.  
  13.     -- Returns 'newstr' only if it contains an integer or is an empty string. 
  14.     -- If 'newstr' contains any non-digit characters then 'curstr' will be 
  15.     -- returned. 
  16.     function Int_Only( curstr, newstr : String ) return String; 
  17.  
  18. end Widgets.Input_Boxes.Constraints;